Process for refining cracked hydrocarbon oil



Patented Jan. 19, 1926.

UNITED STATES PATENT OFFICE.

JACQUE Q'MORRELL, OF CHICAGO, ILLINOIS. ASSIGNOR TO THE UNIVERSAL OIL PROD- UCTS COMPANY, OF CHICAGQ, ILLINOIS, A CORPORATION OF SOUTH DAKOTA.

PROCESS FOR REFINING CRACKED HYDROCARBON OIL.

No Drawing.

To all whom it may concern."

Be it known that I, JACQUE C. MonnELL, a citizen of the United State, residing at No. 208 South La Salle Street, in the city of Chicago, county of Cook, and State of Illinois,

have invented certain new and useful 121K1- provements in Processes; for Refining Cracked Hydrocarbon Oil, of which the following is a specification.

This invention relates to improyements in a process for refining cracked hydrocarbon oils, and refers particularly to cracked hydrocarbon oils having a high sulphur content.

Among the objects of the invention are to provide a process in which the sulphur is extracted from the oil in successive stages,

and the oil subjected to a secondary distillation to produce a refined water white sweet odored product.

Heretofore, it has-been common practice in eliminating objectionable sulphur compounds from hydrocarbon oils to treat the oil with a solution of litharge or lead monoxide in sodium hydroxide in conjunction with sulphur. Few variations of this procedure have been tried, and the reaction itself not carefully observed and considered.

It has been found that sulphur is relatively soluble in hydrocarbon oil, and that the practice of agitating a solution of litharge in sodium hydroxide (sodium plumbite) with the oil to be treated, and adding flowers of sulphur has caused the difficulties in that szme of the sulphur would become dissolved the oil. Upon the addition of sulphur a precipitate containing some lead sulphide is formed. Although not generally known, thereis aconsiderable quantity of the sulphur dissolved in the oil, and is not removed by precipitation, nor can it be taken out'by subsequent water washing.

To avoid this objectionable feature, it is the purpose of this invention to substitute vfor the sulphur various water soluble sulphides, especially the sulphides of potas sium, sodium, and ammonium, or their equivalents including hydrogen sulphide or sulphur dissolved in certain alkalies.

, In treating the oil by'this improved process, one method of procedure may be adopted: The oil may be agitated in the presence of sulphuric acid for say, 15 to 20 minutes,

in the proportion of say, 500 to 650 pounds of acid per 190 barrels of oil, and may then i Application filed August 31, 1922. Serial No. 585,551.

be subjected to treatemcnt with an alkali such as sodium hydoxide or other base, in the arge dissolved in caustic soda,) sodium hydroxide or potassium hydroxide. A suitable proportion might be about five barrels of 163() Baum caustic containing from 5 to 30 pounds of litharge for each 100 barrelsof oil treated. After agitating with the plumbite solution, the latter is removed, and itmay be desirable to wash 'out some/of the remaining traces of the plumbite solution. To the oil then is added a small amount say 4 to 20 pounds per 100 barrels of one of the sulphide solutions, previously mentioned.

This produces a precipitate containing some lead sulphide. This removing of the plumbite solution, and subsequently adding sul- 'phide is an unusual practice, as heretofore the sulphur has been mixed with the oil while the plumbite is contained therein. The

reason for removing the plumbite solution is' that the sulphide reacts with the plumbite solution causing unnecessary waste, and it has been found that when a cracked hydrocarbon oil is treated with a plumbite solution, .a compound of lead soluble in the oil is formed.

After the percipitate is thrown down, it is removed from the oil, and the oil cleaned by subsequent Water washing.

It is then distilled, preferably by steam producing a clear, water white sweet odored distillate. Satisfactory results have been obtained with Mexican, California and Texas oils having a high sulphur content with uniformly good results.

The alkali wash between the sulphuric acid and plumbite treatments inay be dispensed with, in some cases. It is understood that the proportions and concentrati'ons of treating agents used may be varied within wide limits.

I claim as my invention:

1. A. step in a'process for refining hydrocarbon oil consisting in subjecting the oil to an alkali metal plumbite in water solution, agitating the mixture, in then extracting the plumbite solution from the oil, in then introducing sulphide in water solution solution from the oil, in then introducing to the oil, sulphide 1n Water solution to assist the reaction and precipitate sulphur compounds, removing the separated precipitate and excess sulphide.

J ACQUE C. MORRELL. 

